The Human Balance System—

Total Page:16

File Type:pdf, Size:1020Kb

The Human Balance System— PO BOX 13305 · PORTLAND, OR 97213 · FAX: (503) 229-8064 · (800) 837-8428 · [email protected] · WWW.VESTIBULAR.ORG The Human Balance System— A Complex Coordination of Central and Peripheral Systems By the Vestibular Disorders Association, with contributions by Mary Ann Watson, MA, and F. Owen Black, MD, FACS Good balance is often taken for granted. the eye and body muscles. Injury, Most people don’t find it difficult to walk disease, or the aging process can affect across a gravel driveway, transition from one or more of these components. walking on a sidewalk to grass, or get out of bed in the middle of the night without Sensory input stumbling. However, with impaired Maintaining balance depends on infor- balance such activities can be extremely mation received by the brain from three fatiguing and sometimes dangerous. peripheral sources: eyes, muscles and Symptoms that accompany the joints, and vestibular organs (Figure 1). All unsteadiness can include dizziness, three of these sources send information to vertigo, hearing and vision problems, and the brain in the form of nerve impulses difficulty with concentration and memory. from special nerve endings called sensory receptors. What is balance? Balance is the ability to maintain the Input from the eyes body’s center of mass over its base of Sensory receptors in the retina are called support.1 A properly functioning balance rods and cones. When light strikes the system allows humans to see clearly rods and cones, they send impulses to the while moving, identify orientation with brain that provide visual cues identifying respect to gravity, determine direction how a person is oriented relative to other and speed of movement, and make auto- objects. For example, as a pedestrian matic postural adjustments to maintain walks along a city street, the surrounding posture and stability in various conditions buildings appear vertically aligned, and and activities. each storefront passed first moves into and then beyond the range of peripheral Balance is achieved and maintained by vision. a complex set of sensorimotor control systems that include sensory input from Input from the muscles and joints vision (sight), proprioception (touch), and Proprioceptive information from the skin, the vestibular system (motion, equilibri- muscles, and joints involves sensory um, spatial orientation); integration of receptors that are sensitive to stretch or that sensory input; and motor output to pressure in the surrounding tissues. For © Vestibular Disorders Association ◦ www.vestibular.org ◦ Page 1 of 5 example, increased pressure is felt in the Proprioceptive cues from the neck indicate front part of the soles of the feet when a the direction in which the head is turned. standing person leans forward. With any Cues from the ankles indicate the body’s movement of the legs, arms, and other movement or sway relative to both the body parts, sensory receptors respond by standing surface (floor or ground) and the sending impulses to the brain. quality of that surface (for example, hard, soft, slippery, or uneven). The sensory impulses originating in the neck and ankles are especially important. Input from the vestibular system Sensory information about motion, particular canal, the endolymphatic fluid equilibrium, and spatial orientation is within it lags behind because of inertia provided by the vestibular apparatus, and exerts pressure against the canal’s which in each ear includes the utricle, sensory receptor. The receptor then sends saccule, and three semicircular canals. impulses to the brain about movement. The utricle and saccule detect gravity When the vestibular organs on both sides (vertical orientation) and linear of the head are functioning properly, they movement. The semicircular canals, which send symmetrical impulses to the brain. detect rotational movement, are located (Impulses originating from the right side at right angles to each other and are filled are consistent with impulses originating with a fluid called endolymph. When the from the left side.) head rotates in the direction sensed by a © Vestibular Disorders Association ◦ www.vestibular.org ◦ Page 2 of 5 Integration of sensory input provided by the vestibular organs may Balance information provided by the help override this sensory conflict. In peripheral sensory organs—eyes, muscles addition, higher level thinking and and joints, and the two sides of the memory might compel the person to vestibular system—is sent to the brain glance away from the moving bus to look stem. There, it is sorted out and inte- down in order to seek visual confirmation grated with learned information that his body is not moving relative to the contributed by the cerebellum (the pavement. coordination center of the brain) and the cerebral cortex (the thinking and memory Motor output center). The cerebellum provides As sensory integration takes place, the information about automatic movements brain stem transmits impulses to the that have been learned through repeated muscles that control movements of the exposure to certain motions. For example, eyes, head and neck, trunk, and legs, by repeatedly practicing serving thus allowing a person to both maintain a ball, a tennis player learns to optimize balance and have clear vision while balance control during that movement. moving. Contributions from the cerebral cortex include previously learned information; Motor output to the muscles and joints for example, because icy sidewalks are A baby learns to balance through practice slippery, one is required to use a different and repetition as impulses sent from the pattern of movement in order to safely sensory receptors to the brain stem and navigate them. then out to the muscles form a new path- way. With repetition, it becomes easier Processing of conflicting for these impulses to travel along that sensory input nerve pathway—a process called A person can become disoriented if the facilitation—and the baby is able to sensory input received from his or her maintain balance during any activity. eyes, muscles and joints, or vestibular Strong evidence exists suggesting that organs sources conflicts with one another. such synaptic reorganization occurs For example, this may occur for example, throughout a person’s lifetime of when a person is standing next to a bus adjusting to changing motion environs. that is pulling away from the curb. The visual image of the large rolling bus may This pathway facilitation is the reason create an illusion for the pedestrian that dancers and athletes practice so he or she—rather than the bus—is arduously. Even very complex movements moving. However, at the same time the become nearly automatic over a period of proprioceptive information from his time. muscles and joints indicates that he is not actually moving. Sensory information For example, when a person is turning © Vestibular Disorders Association ◦ www.vestibular.org ◦ Page 3 of 5 cartwheels in a park, impulses systems. Its interlacing feedback mecha- transmitted from the brain stem inform nisms can be disrupted by damage to one the cerebral cortex that this particular or more components through injury, activity is appropriately accompanied by disease, or the aging process. Impaired the sight of the park whirling in circles. balance can be accompanied by other With more practice, the brain learns to symptoms such as dizziness, vertigo, interpret a whirling visual field as normal vision problems, nausea, fatigue, and during this type of body rotation. concentration difficulties. Alternatively, dancers learn that in order to maintain balance while performing a The complexity of the human balance series of pirouettes, they must keep their system creates challenges in diagnosing eyes fixed on one spot in the distance as and treating the underlying cause of long as possible while rotating their body. imbalance. Vestibular dysfunction as a cause of imbalance offers a particularly Motor output to the eyes intricate challenge because of the The vestibular system sends motor control vestibular system’s interaction with signals via the nervous system to the cognitive functioning,2 and the degree of muscles of the eyes with an automatic influence it has on the control of eye function called the vestibulo-ocular reflex. movements and posture. When the head is not moving, the number of impulses from the vestibular organs on References the right side is equal to the number of 1. Shumway-Cook A, Woollacott MH. impulses coming from the left side. When Motor Control: Theory and Practical the head turns toward the right, the num- Applications. Philadelphia: Lippincott, ber of impulses from the right ear Williams & Wilkins; 2001. increases and the number from the left 2. Hanes DA, McCollum G. Journal of ear decreases. The difference in impulses Vestibular Research 2006;16(3):75–91. sent from each side controls eye movements and stabilizes the gaze during © 2008 Vestibular Disorders Association active head movements (e.g., while VEDA’s publications are protected under running or watching a hockey game) and copyright. For more information, see our passive head movements (e.g., while permissions guide at www.vestibular.org. sitting in a car that is accelerating or This document is not intended as a decelerating). substitute for professional health care. The coordinated balance system The human balance system involves a complex set of sensorimotor-control © Vestibular Disorders Association ◦ www.vestibular.org ◦ Page 4 of 5 PO BOX 13305 · PORTLAND, OR 97213 · FAX: (503) 229-8064
Recommended publications
  • Vestibular Sensory Dysfunction: Neuroscience and Psychosocial Behaviour Overview
    DOI: 10.21277/sw.v2i6.263 VESTIBULAR SENSORY DYSFUNCTION: NEUROSCIENCE AND PSYCHOSOCIAL BEHAVIOUR OVERVIEW Brigita Kreivinienė Dolphin Assisted Therapy Center, Klaipėda University, Lithuania Abstract The objective of the submitted contribution is to describe one of the sensory dysfunctions – the dysfunction of the vestibular system. The vestibular system is a crucial sensory system for other sensory systems such as tactile and proprioception, as well as having tight connection to the limbic system. Vestibular sensory system has a significant role for further physical, emotional and psychosocial development. Descriptive method and case analysis are applied in literature based research methodology. These methods are most appropriate as far the vestibular dysfunctions are not always recognized in young age even though they are seen as high psychoemotional reactions (psychosocial behavior). The vestibular dysfunctions in young age can be scarcely noticeable as far more often they tend to look like “just high emotional reactions” as crying, withdrawal, attachment to mother etc. which could be sensed as a normal reaction of a young child. Detailed vestibular sensory dysfunction analysis is presented, as well as the explanation of the neurological processes, and predictions are made for the further possible interventions. Keywords: vestibular dysfunction, neuroscience, psychosocial behavior. Introduction Some problems, such as broken bones, cerebral palsy or poor eyesight are obvious. Others, such as underlying poor behavior or slow learning are not so obvious. The issues, such as awkward walking, fear of other children, complicated socialization, unsecured feeling at school, avoidance of swings or climbing, slapping on the floor or to any other object, attachment to mother, sensitivity to changes in walking surfaces, preference on the same footwear (if changed, often falling/takes time to adapt), aggression to others, stimulation of head rotation, hyperactivity or constant distraction by light, smell, sound etc., and any others can have underlying sensory issues.
    [Show full text]
  • How Does the Balance System Work?
    How Does the Balance System Work? Author: Shannon L.G. Hoffman, PT, DPt Sara MacDowell PT, DPT Fact Sheet Many systems work together to help you keep your balance. The goal is to keep your body and vision stable Peripheral Sensory Systems: 1) Vision: Your vision helps you see where your head and body are in rela- tion to the world around you. 2) Somatosensory/Proprioception: We use the feeling from our feet against the ground as well as special sensors in our joints to know where our feet and legs are positioned. It also tells how your head is oriented to your neck and shoulders. Produced by 3) Vestibular system: Balance organs in the inner ear tell the brain about the movements and position of your head. There are 3 canals in each ear that sense when you move your head and help keep your vision clear. Central Processing: Information from these 3 systems is sent to the brain for processing. The brain stem also gets information from other parts of the brain called the cerebellum and cerebral cortex, mostly about past experiences that have A Special Interest affected your sense of balance. Your brain can control balance by using Group of the information that is most important for a certain situation. For example, in the dark, when you can’t use your vision, your brain will use more information from your legs and feet and your inner ear. If you are walking on a sandy beach during the day, you can’t trust your feet on the ground and your brain will use your eyes and inner ear more.
    [Show full text]
  • Understanding Sensory Processing: Looking at Children's Behavior Through the Lens of Sensory Processing
    Understanding Sensory Processing: Looking at Children’s Behavior Through the Lens of Sensory Processing Communities of Practice in Autism September 24, 2009 Charlottesville, VA Dianne Koontz Lowman, Ed.D. Early Childhood Coordinator Region 5 T/TAC James Madison University MSC 9002 Harrisonburg, VA 22807 [email protected] ______________________________________________________________________________ Dianne Koontz Lowman/[email protected]/2008 Page 1 Looking at Children’s Behavior Through the Lens of Sensory Processing Do you know a child like this? Travis is constantly moving, pushing, or chewing on things. The collar of his shirt and coat are always wet from chewing. When talking to people, he tends to push up against you. Or do you know another child? Sierra does not like to be hugged or kissed by anyone. She gets upset with other children bump up against her. She doesn’t like socks with a heel or toe seam or any tags on clothes. Why is Travis always chewing? Why doesn’t Sierra liked to be touched? Why do children react differently to things around them? These children have different ways of reacting to the things around them, to sensations. Over the years, different terms (such as sensory integration) have been used to describe how children deal with the information they receive through their senses. Currently, the term being used to describe children who have difficulty dealing with input from their senses is sensory processing disorder. _____________________________________________________________________ Sensory Processing Disorder
    [Show full text]
  • Saccule and Utricle
    THE SPECIAL SENSES VESTIBULAR FUNCTION DR SYED SHAHID HABIB MBBS DSDM PGDCR FCPS Professor Dept. of Physiology College of Medicine & KKUH OBJECTIVES At the end of this lecture you should be able to describe: Functional anatomy of Vestibular apparatus Dynamic and static equilibrium Role of utricle and saccule in linear acceleration Role of semicircular canals in angular motions Vestibular Reflexes Overview of Static Proprioception & Balance position sense (Ia) Dynamic position sense (II) Static Equilibrium Utricle & Saccule Neck Proprioceptors Linear Acceleration Horizontal (Utricle) Visual Information (vesitbulo Ocular) Linear Acceleration Vestibular Apparatus Horizontal (Saccule) Proprioception Chest Wall Equilibrium Angular Acceleration Proprioceptors (SCCs) air pressure against body Predictive Functions (SCCs) Footpads pressure To balance the centre of gravity must be above the support point. Centre of gravity Physiology Of Body Balance Balance & Equilibrium Balance is the ability to maintain the equilibrium of the body • Foot position affects standing balance Equilibrium is the state of a body or physical system at rest or in un accelerated motion in which the resultant of all forces acting on it is zero and the sum of all torques about any axis is zero. There are 2 types of Equilibrium » Static - » Dynamic – Static Equilibrium keep the body in a desired position Static equilibrium –The equilibrium is maintained in a FIXED POSITION, usually while stood on one foot or maintenance of body posture relative to gravity while the body is still. Dynamic Equilibrium to move the body in a controlled way Dynamic equilibrium The equilibrium must be maintained while performing a task which involves MOVEMENT e.g. Walking the beam.
    [Show full text]
  • Common Vestibular Function Tests
    Common Vestibular Function Tests Authors: Barbara Susan Robinson, PT, DPT; Lisa Heusel-Gillig PT DPT NCS Fact Sheet The purpose of Vestibular Function Tests (VFTs) is to determine the health of the vestibular portion of the inner ear. These tests are commonly performed by ENTs, Audiologists, and Otolaryngologists Electronystagmography or Videonystagmography Electronystagmography (ENG test) or Videonystagmography (VNG test) evaluate the inner ear. Both record eye movements during a group of tests in light and dark rooms. During the ENG test, small electrodes are placed on the skin near the eyes to record eye movements. For the VNG test, eye movements are recorded by a video camera mounted inside of goggles that are worn during testing. ENG and VNG tests evaluate eye movements while following a visual target (tracking Produced by test) or during body and head position changes (positional test). The caloric test evaluates eye movements in response to cool or warm air (or water) placed in the ear canal. If there is no response to warm or cool air or water, ice water may be used in order to try to produce a response. The caloric test determines the difference between the function of the left and right inner ear. During this test, you may experience dizziness or nausea. You may be asked questions (math questions, city names, alphabet tasks) to distract you in order to get the best results. A Special Interest Group of Contact us: ANPT Other Common Vestibular Function Tests 5841 Cedar Lake Rd S. The rotary chair test is used along with the VNG to confirm the diagnosis and assess Ste 204 compensation of the vestibular system.
    [Show full text]
  • Organ of Corti Size Is Governed by Yap/Tead-Mediated Progenitor Self-Renewal
    Organ of Corti size is governed by Yap/Tead-mediated progenitor self-renewal Ksenia Gnedevaa,b,1, Xizi Wanga,b, Melissa M. McGovernc, Matthew Bartond,2, Litao Taoa,b, Talon Treceka,b, Tanner O. Monroee,f, Juan Llamasa,b, Welly Makmuraa,b, James F. Martinf,g,h, Andrew K. Grovesc,g,i, Mark Warchold, and Neil Segila,b,1 aDepartment of Stem Cell Biology and Regenerative Medicine, Keck Medicine of University of Southern California, Los Angeles, CA 90033; bCaruso Department of Otolaryngology–Head and Neck Surgery, Keck Medicine of University of Southern California, Los Angeles, CA 90033; cDepartment of Neuroscience, Baylor College of Medicine, Houston, TX 77030; dDepartment of Otolaryngology, Washington University in St. Louis, St. Louis, MO 63130; eAdvanced Center for Translational and Genetic Medicine, Lurie Children’s Hospital of Chicago, Chicago, IL 60611; fDepartment of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX 77030; gProgram in Developmental Biology, Baylor College of Medicine, Houston, TX 77030; hCardiomyocyte Renewal Laboratory, Texas Heart Institute, Houston, TX 77030 and iDepartment of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030; Edited by Marianne E. Bronner, California Institute of Technology, Pasadena, CA, and approved April 21, 2020 (received for review January 6, 2020) Precise control of organ growth and patterning is executed However, what initiates this increase in Cdkn1b expression re- through a balanced regulation of progenitor self-renewal and dif- mains unclear. In addition, conditional ablation of Cdkn1b in the ferentiation. In the auditory sensory epithelium—the organ of inner ear is not sufficient to completely relieve the block on Corti—progenitor cells exit the cell cycle in a coordinated wave supporting cell proliferation (9, 10), suggesting the existence of between E12.5 and E14.5 before the initiation of sensory receptor additional repressive mechanisms.
    [Show full text]
  • Recognizing Vestibular Problems in Children
    Recognizing Vestibular Problems in Children Author: Jennifer Braswell Christy, PT, PhD Fact Sheet What is the vestibular system? The vestibular system is a tiny organ located in each inner ear that helps with balance and allows steady vision during head movements. The cochlea (hearing organ) is closely linked to the vestibular system and therefore children who are born with severe hearing loss might also have balance problems. Migraine syndrome can cause temporary sensations of spinning (vertigo), motion sensitivity and poor balance, related to the vestibular system. Middle ear infections (otitis media) can also cause poor balance and clumsiness that gets better following placement tubes in the ear. Produced by How can I recognize a vestibular problem in my child? Children with vestibular problems might have poor balance leading to falls, especially during high level activities (eg, hopping, skipping and walking on a balance beam). Babies with vestibular problems are typically delayed in learning to sit, stand and walk. Although children A Special Interest rarely complain, they might also have trouble focusing their eyes Group of during head movement (eg, reading a sign when walking). If inner ear function is suddenly lost on one side, the eyes will beat quickly away from the damaged side and your child might complain of spinning. This can happen right after a child has cochlear implant surgery. The dizziness and quick jerking of the eyes should go away after a few days but the imbalance and problems focusing may stay. Migraine can cause symptoms such as headache, spinning, balance problems, ringing in the ears and difficulty speaking.
    [Show full text]
  • Anatomy of the Ear ANATOMY & Glossary of Terms
    Anatomy of the Ear ANATOMY & Glossary of Terms By Vestibular Disorders Association HEARING & ANATOMY BALANCE The human inner ear contains two divisions: the hearing (auditory) The human ear contains component—the cochlea, and a balance (vestibular) component—the two components: auditory peripheral vestibular system. Peripheral in this context refers to (cochlea) & balance a system that is outside of the central nervous system (brain and (vestibular). brainstem). The peripheral vestibular system sends information to the brain and brainstem. The vestibular system in each ear consists of a complex series of passageways and chambers within the bony skull. Within these ARTICLE passageways are tubes (semicircular canals), and sacs (a utricle and saccule), filled with a fluid called endolymph. Around the outside of the tubes and sacs is a different fluid called perilymph. Both of these fluids are of precise chemical compositions, and they are different. The mechanism that regulates the amount and composition of these fluids is 04 important to the proper functioning of the inner ear. Each of the semicircular canals is located in a different spatial plane. They are located at right angles to each other and to those in the ear on the opposite side of the head. At the base of each canal is a swelling DID THIS ARTICLE (ampulla) and within each ampulla is a sensory receptor (cupula). HELP YOU? MOVEMENT AND BALANCE SUPPORT VEDA @ VESTIBULAR.ORG With head movement in the plane or angle in which a canal is positioned, the endo-lymphatic fluid within that canal, because of inertia, lags behind. When this fluid lags behind, the sensory receptor within the canal is bent.
    [Show full text]
  • The Human Balance System: a Complex Coordination Of
    The Human Balance ANATOMY System: A Complex Coordination of Central and Peripheral Systems By Vestibular Disorders Association, with contributions by Mary Ann BALANCE Watson, MA, F. Owen Black, MD, FACS, and Matthew Crowson, MD To maintain balance we use input from our vision Good balance is often taken for granted. Most people don’t find it difficult (eyes), proprioception to walk across a gravel driveway, transition from walking on a sidewalk (muscles/joints), to grass, or get out of bed in the middle of the night without stumbling. and vestibular system However, with impaired balance such activities can be extremely fatiguing (inner ear). and sometimes dangerous. Symptoms that accompany the unsteadiness can include dizziness, vertigo, hearing and vision problems, and difficulty with concentration and memory. ARTICLE WHAT IS BALANCE? Balance is the ability to maintain the body’s center of mass over its base of support. 1 A properly functioning balance system allows humans to see clearly while moving, identify orientation with respect to gravity, determine direction and speed of movement, and make automatic postural adjustments to maintain posture and stability in various 036 conditions and activities. Balance is achieved and maintained by a complex set of sensorimotor control systems that include sensory input from vision (sight), DID THIS ARTICLE proprioception (touch), and the vestibular system (motion, equilibrium, HELP YOU? spatial orientation); integration of that sensory input; and motor output SUPPORT VEDA @ to the eye and body muscles. Injury, disease, certain drugs, or the aging VESTIBULAR.ORG process can affect one or more of these components. In addition to the contribution of sensory information, there may also be psychological factors that impair our sense of balance.
    [Show full text]
  • Visual-Vestibular Coordination
    Visual-Vestibular Coordination The visual and vestibular systems share an inseparable neurological and functional connection. Together they provide the foundation for skillful and comfortable movement through space and time as well as for efficient intake of visual information for learning. Although vestibular functions and oculomotor control are typically addressed in sensory integration treatment, the efficient coordination of these systems is more recently being targeted in treatment for enhanced functional visual skills. Your therapist here at OTA The Koomar Center (OTA) may be talking to you about incorporating such focused activities within treatment sessions and within a home program. The vestibular system is often referred to as the movement or balance system. The receptors are located within the inner ear, and respond to gravity and detect motion and change of head position. They tell us where we are in relationship to gravity, if we are moving or at rest, and our speed and direction of movement. The vestibular system is a powerful integrator that interacts with all other sensory systems. It most noticeably impacts our posture, balance, muscle tone, and bilateral coordination. The visual system is more than just eyesight, or the ability to see clearly. It is also our ability to understand what we see. It is estimated that at least 75% of learning occurs through visual pathways. If an individual is experiencing any visual difficulties, learning will most likely be impacted. For efficient oculomotor function, complex integration of many sensory systems must occur. According to Josephine Moore, the vestibular system is like a tripod stand that holds a camera, in that it helps hold the head stable so that the eyes can focus on an object.
    [Show full text]
  • Balance and Equilibrium, I: the Vestibule and Semicircular Canals
    Anatomic Moment Balance and Equilibrium, I: The Vestibule and Semicircular Canals Joel D. Swartz, David L. Daniels, H. Ric Harnsberger, Katherine A. Shaffer, and Leighton Mark In this, our second temporal bone installment, The endolymphatic duct arises from the en- we will emphasize the vestibular portion of the dolymphatic sinus and passes through the ves- labyrinth, that relating to balance and equilib- tibular aqueduct of the osseous labyrinth to rium. Before proceeding, we must again remind emerge from an aperture along the posterior the reader of the basic structure of the labyrinth: surface of the petrous pyramid as the endolym- an inner membranous labyrinth (endolym- phatic sac. phatic) surrounded by an outer osseous laby- The utricle and saccule are together referred rinth with an interposed supportive perilym- to as the static labyrinth, because their function phatic labyrinth. We recommend perusal of the is to detect the position of the head relative to first installment before continuing if there are gravity (5–7). They each have a focal concen- any uncertainties in this regard. tration of sensory receptors (maculae) located The vestibule, the largest labyrinthine cavity, at right angles to each other and consisting of measures 4 to 6 mm maximal diameter (1–3) ciliated hair cells and tiny crystals of calcium (Figs 1–3). The medial wall of the vestibule is carbonate (otoliths) embedded in a gelatinous unique in that it contains two distinct depres- mass. These otoliths respond to gravitational sions (Fig 4). Posterosuperiorly lies the elliptical pull; therefore, changes in head position distort recess, where the utricle is anchored.
    [Show full text]
  • 7 Senses Street Day Bringing the Common Sense Back to Our Neighbourhoods
    7 Senses Street Day Bringing the common sense back to our neighbourhoods Saturday, 16 November 2013 What are the 7 Senses? Most of us are familiar with the traditional five senses – sight, smell, taste, hearing, and touch. The two lesser known senses refer to our movement and balance (Vestibular) and our body position (Proprioception). This article gives an overview of each of the senses and how the sensory processing that occurs for us to interpret the world around us. Quick Definitions Sensory integration is the neurological process that organizes sensations from one's body and from the environment, and makes it possible to use the body to make adaptive responses within the environment. To do this, the brain must register, select, interpret, compare, and associate sensory information in a flexible, constantly-changing pattern. (A Jean Ayres, 1989) Sensory Integration is the adequate and processing of sensory stimuli in the central nervous system – the brain. It enables us interact with our environment appropriately. Sensory processing is the brain receiving, interpreting, and organizing input from all of the active senses at any given moment. For every single activity in daily life we need an optimal organization of incoming sensory information. If the incoming sensory information remains unorganized – e.g. the processing in the central nervous system is incorrect - an appropriate, goal orientated and planned reaction (behavior) relating to the stimuli is not possible. Sight Sight or vision is the capability of the eyes to focus and detect images of visible light and generate electrical nerve impulses for varying colours, hues, and brightness.
    [Show full text]